It has become increasingly important to monitor temperatures within electronic circuitry (e.g., on an integrated circuit (“IC”) die, or chip). For example, it is important to manage the on-die temperature in a multi-core SOC (“system on chip”) due to issues pertaining to the positive feedback mechanism associated with leakage current and temperature, in that leakage current results in increases in temperature within the die circuitry. A temperature sensor can be used to monitor the temperature of an electronic component, such as a CPU (“central processing unit”), GPU (“graphics processing unit”), MPU (“microprocessor unit”), SOC (“system on chip”), etc. When the temperature exceeds a predetermined threshold, the temperature sensor can alert circuitry to slow down (or even shut down) the electronic component to reduce power consumption, and thus reduce the temperature so that overheating that can cause destructive failure to the electronic component may be prevented.
Typically, temperature sensors include a reference circuit and temperature measuring circuitry, wherein the temperature dependency is either proportional to absolute temperature (“PTAT”), wherein the measuring circuit outputs a voltage that increases in proportion to a rise in temperature at the location of the electronic circuitry in which the temperature sensor is located (i.e., has a positive temperature coefficient), or complementary to absolute temperature (“CTAT”), wherein the measuring circuit outputs a voltage that decreases in proportion to a rise in temperature at the location of the electronic circuitry in which the temperature sensor is located (i.e., has a negative temperature coefficient). Further, DAC (“digital-to-analog converter”) based temperature sensors have been implemented relying on comparing a PTAT voltage and a CTAT base-emitter voltage. This approach, however, has suffered from DAC code-to-temperature non-linearity issues; that is, such temperature sensors cannot achieve good linearity over a wide temperature range, resulting in poor temperature measurement accuracy.